/usr/share/gtk-doc/ is in libxfce4util-dev 4.12.1-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gtk-doc/html/
/usr/share/gtk-doc/html/libxfce4util/
/usr/share/gtk-doc/html/libxfce4util/home.png
/usr/share/gtk-doc/html/libxfce4util/index.html
/usr/share/gtk-doc/html/libxfce4util/index.sgml
/usr/share/gtk-doc/html/libxfce4util/left-insensitive.png
/usr/share/gtk-doc/html/libxfce4util/left.png
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-File-Utilities.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Internationalisation.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Miscellaneous-Utilities.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-POSIX-Signal-Handling.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Resource-Config-File-Support.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Resource-lookup-functions.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Software-Licenses.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Unicode-Support-Functions.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Version-Information.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Xfce-Generics.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-Xfce-Kiosk-functions.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-core.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-datatypes.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-fundamentals.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util-utilities.html
/usr/share/gtk-doc/html/libxfce4util/libxfce4util.devhelp2
/usr/share/gtk-doc/html/libxfce4util/reference.html
/usr/share/gtk-doc/html/libxfce4util/right-insensitive.png
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